1315679021 has 4 divisors (see below), whose sum is σ = 1316845500. Its totient is φ = 1314512544.

The previous prime is 1315679017. The next prime is 1315679033. The reversal of 1315679021 is 1209765131.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 677560900 + 638118121 = 26030^2 + 25261^2 .

It is a cyclic number.

It is not a de Polignac number, because 1315679021 - 2² = 1315679017 is a prime.

It is a super-2 number, since 2×1315679021² = 3462022572599036882, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1315679081) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 581546 + ... + 583803.

It is an arithmetic number, because the mean of its divisors is an integer number (329211375).

Almost surely, 2^1315679021 is an apocalyptic number.

It is an amenable number.

1315679021 is a deficient number, since it is larger than the sum of its proper divisors (1166479).

1315679021 is a wasteful number, since it uses less digits than its factorization.

1315679021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1166478.

The product of its (nonzero) digits is 11340, while the sum is 35.

The square root of 1315679021 is about 36272.2899883644. The cubic root of 1315679021 is about 1095.7630457805.

The spelling of 1315679021 in words is "one billion, three hundred fifteen million, six hundred seventy-nine thousand, twenty-one".